1. Field of the Invention
The present invention relates to a copying apparatus which senses the size of an original to be copied and which produces a copy of this original according to the sensed size.
2. Description of the Prior Art
Copying apparatuses are generally capable of reproducing images of an original on recording media such as recording paper sheets of various sizes. In order to select or change the size of the copying media, the operator sets a copying medium of desired size in the copying apparatus. In a copying apparatus in which copying media of different sizes can be set, the operator depresses a size selection switch or the like on a control panel in order to select or change the size of the copying medium.
However, with these conventional copying apparatuses, the operator himself must confirm the size of the original first and then set or select a copying medium of the corresponding size.
For this reason, when the operator erroneously sets or selects the size of the copying medium or forgets to do so, the image of the original is reproduced on a copying medium of inappropriate size, resulting in inefficient operation.
In view of this problem, a copying apparatus has been proposed which has an automatic selection mechanism for automatically selecting a copying medium of one size from recording media of a plurality of sizes in accordance with the sensed size of the original.
However, unlike the copying media, the originals have divergent shapes and sizes, so that the automatic selection mechanism may not properly function.
Other conventional copying apparatuses have been proposed such as a copying apparatus which has an ADF (Automatic Document Feeder) for automatically feeding an original to an exposure position, or a copying apparatus in which the operator places the original at the exposure position and covers it with an original mat. The former copying apparatus is advantageous in that time required for setting and resetting originals may be significantly reduced.
In addition to this advantage, the ADF also serves to improve the operability, to eliminate erroneous copying operations, and to eliminate loss or damage to the original during copying operations. The ADF thus facilitates the copying operation.
However, these advantages of the ADF are obtained only if originals of one size are fed to the exposure position. The size of the copying medium must be switched every time an original of different size is fed. Although such a switching operation itself is simple in procedure, it may be simply forgotton by the operator in a rather monotonous series of copying operations. The operator may find out his error only after the apparatus has reproduced a copy in a wrong size.
When the operator is not accustomed to the operation system of the apparatus, he or she may find out the error only after a plurality of copies has been reproduced in a wrong size. If the image of each original is reproduced on a plurality of copying media, such erroneous operation results in waste of the copying medium. This waste is further promoted since a copying apparatus with an ADF is generally a high-speed apparatus. Although such as erroneous operation may be eliminated to the minimum by training of the operators, it is, of course, preferable that the apparatus itself be capable of preventing such an error.